Transparent aqueous compositions comprising hydrophobic silicone oils

ABSTRACT

The invention relates to optically transparent aqueous compositions containing hydrophobic silicone oil and a comparably low amount of wash-active matter, being suitable as a hair treatment composition such as a shampoo. In particular, it provides an optically transparent aqueous composition comprising (a) a hydrophobic silicone oil in an amount of 1-3 wt.-% with respect to the total weight of the composition; (b) a solubilizer for the silicone oil; and (d) an anionic surfactant; wherein the weight-ratio of component (b) to component (a) is in the range of 1:1 to 12:1; and wherein the total amount of the components (b) and (c) is in the range of 10-25 wt.-% with respect to the total weight of the composition. The invention also provides a method for preparing the above composition.

[0001] The present invention relates to optically transparent aqueouscompositions containing hydrophobic silicone oil and a comparably lowamount of wash-active matter, the compositions being suitable as a hairtreatment composition such as a shampoo.

[0002] Due to their very low surface tension, the spreadability ofsilicone oils on most surfaces such as ceramics, textiles, paper, skin,and hair, is excellent. In the field of personal care products, siliconeoils are used because of their hair and skin smoothing properties, hairgloss enhancing properties and skin feel improving (non-oily, silky skinfeel) properties. For many decades they are therefore ingredients inhairsprays, conditioners, colorants and sun protecting creams. Incosmetic rinse-off products like shampoos they appeared in the 1980iesand could obtain a considerable market share in the early 1990ies in theso-called “two-in-one” shampoos. These shampoos contain emulsifiedsilicone oils. Silicone oil emulsions, however, show problems withrespect to compatibility and stability, they show a strong foaminessreducing effect and furthermore they are generally not transparent. Thisis why hydrophilic silicone polyethers have been introduced into themarket. But apart from their generally higher price, the conditioningeffect of hydrophilic silicone polyethers on skin and hair is generallymuch lower than of the hydrophobic silicone oils.

[0003] In view of these problems, attempts have been made to provideaqueous compositions containing hydrophobic silicone oil, the siliconeoil being in a solubilized or micro-emulsified state. U.S. Pat. No.6,013,683 describes a microemulsion containing 40 to 95 wt. % of a shortchain linear siloxane and water, and 5 to 60 wt. % of non-ionic and/orcationic surfactants. However, the microemulsions disclosed in thispatent are only transparent in a very narrow temperature range andeasily become turbid when added to aqueous solutions.

[0004] EP 0 529 883 B1 discloses hair shampoo compositions containingsodium lauryl ether sulfate and cocoamido propyl betaine as surfactantsand 1.0 wt.-% of silicone oil. The silicone oil was added asmicro-emulsion prepared by an emulsion polymerization technique. Hence,EP 0 529 883 B1 does not disclose aqueous compositions containingsilicone oil which may be easily prepared.

[0005] On the other hand, the inventors of the present inventionpreviously published a method allowing the easy incorporation ofsilicone oil into shampoos (H. Denzer, R. Jansen, M. Reininghaus in“Parfümerie und Kosmetik”; June 1999 pages 18-20). However, the methodonly allowed for the incorporation of comparably low amounts of siliconeoil such as 0.5 wt.-% when using wash-active matter within the range of15-40 wt.-%. Higher amounts of hydrophobic silicone oil could only besolubilized by increasing the amount of wash-active matter which is,however, not acceptable for dermatological and environmental reasons aswell as for price reasons.

[0006] In view of these drawbacks of the prior art, it is the objectunderlying the present invention to provide an easily preparable,optically transparent aqueous composition being suitable as hair shampoocontaining an increased amount of hydrophobic silicone oil.

[0007] This object of the present invention is solved by the provisionof an optically transparent aqueous composition comprising

[0008] (a) a hydrophobic silicone oil in an amount of 1-3 wt.-% withrespect to the total weight of the composition;

[0009] (b) a solubilizer for the silicone oil; and

[0010] (c) an anionic surfactant;

[0011] wherein the weight ratio of component (b) to component (a) is inthe range of 1:1 to 10:1; and wherein the total amount of the components(b) and (c) is in the range of 10-25 wt.-% with respect to the totalweight of the composition.

[0012] A hydrophobic silicone oil is generally a silicone oil which issoluble in paraffinic oil at 25° C. Hydrophobic silicone oils to be usedaccording to the present invention include both volatile andnon-volatile silicone oils.

[0013] Specific examples include a cyclic methyl siloxane having theformula {(CH₃)₂SiO}_(x) in which x is 3-6, or short chain linear methylsiloxanes having the formula

((CH₃)₂SiO((CH₃)₂SiO)_(y)Si(CH₃)₃ in which y is 0-5.

[0014] Some suitable cyclic methyl siloxanes arehexamethylcyclotrisiloxanes (D₃), a solid with a boiling point of 134°C. and the formula {(Me₂)SiO}₃; octamethylcyclotetrasiloxane (D₄) with aboiling point of 176° C., a viscosity of 2.3 mm²/s, and the formula{(Me₂)SiO}₄; decamethylcyclopentasiloxane (D₅) (cyclomethicone) with aboiling point of 210° C., a viscosity of 3.87 mm²/s, and the formula{(Me₂)SiO}₅; and dodecamethylcyclohexasiloxane (D₆) with a boiling pointof 245° C., a viscosity of 6.62 mm²/s and the formula {(Me₂)SiO}₆.

[0015] Some suitable short linear methyl siloxane arehexamethyldisiloxane (MM) with a boiling point of 100° C., viscosity of0-65 mm²/s, and formula Me₃SiOMe₃; octamethyltrisiloxane (MDM) with aboiling point of 152° C., viscosity of 1.04 mm²/s, and formulaMe₃SiOMe₂SiOsiMe₃; decamethyltetrasiloxane (MD₂M) with a boiling pointof 194° C., viscosity of 1.53 mm²/s, and formula Me₃SiO(MeSiO)₂SiMe₃;dodecamethylpentasiloxane (MD₃M) with a boiling point of 229° C.,viscosity of 2.06 mm₂/s; and formula Me₃SiO(Me₂SiO)₃SiMe₃;tetradecamethylhexasiloxane (MD₄M) with a boiling point of 245° C.,viscosity of 2.63 mm2/s, and formula Me₃SiO(Me₂SiO)₄SiMe₃; andhexadecamethylheptasiloxane (MD₅M) with a boiling point of 270° C.,viscosity of 3.24 mm²/s, and formula Me₃SiO(Me₂SiO)₅SiMe₃.

[0016] Furthermore, long chain linear siloxanes such asphenyltrimethicone, bis(phenylpropyl)dimethicone, dimethicone, anddimethiconol are also included.

[0017] The amount of the hydrophobic silicone oil is 1-3 wt.-%,preferably 1.5 wt. % to 3 wt. % with respect to the total weight of thecomposition.

[0018] The composition of the present invention further contains asolubilizer for the silicone oil. The term “solubilizer”, in the contextof the present invention, refers to a surfactant which allows thesolubilization of the hydrophobic silicone oil or the formation of amicro-emulsion of the hydrophobic silicone oil in an aqueous phase.Solubilization is defined as the spontaneous dissolving of a substanceby the reversible interaction with the micelles of a surfactant in asolvent to form a thermodynamically stable isotropic solution withreduced thermodynamic activity of the solubilized material (see“Surfactants and Interfacial Phenomena”, by Milton T. Rosen, ed. JohnWiley & Sons (1978), Chapter 4, page 123). This isotropic solution isgenerally a single phase clear microemulsion which forms spontaneouslyin the sense that it does not require a high energy input by means ofhigh shear devices. Thus, a turbine, impeller, colloid mill,homogenizer, or sonicator, is not required to form these systems. It isonly necessary that the appropriate amounts of the three componentswater, silicone oil, and solubilizer be added to a suitable container,and the container is either hand shaken, or gently stirred by means of alaboratory magnetic stirrer at a temperature below 30° C. Of course, thecomponents can be mixed or sheared with more energy input, and the clearsingle phase system will still be obtained, but no advantage resultsfrom such additional energy usage.

[0019] The solubilization property of a surfactant or surfactant mixturecan be easily determined by placing the surfactant/surfactant mixture,silicone oil, such as Cyclomethicone and possibly water in a vessel,e.g. in a total volume of 100 ml. The weight ratio of solubilizer tosilicone oil may be in the range of 1:1 to 12:1. Then, a magnetic bar isintroduced into the vessel, and the vessel is placed on top of amagnetic stirrer such as IKAMAG (supplied by Janke&Kunkel, Germany).Subsequently, the mixture is stirred at a maximum of 400 RPM, preferably200 RPM at a temperature of 20° C. or less for some minutes, e.g. 5minutes. 400 RPM correspond approximately to an energy input of 50 W. Ifthe mixture thus obtained has formed an optically transparenthomogeneous solution, the surfactant/surfactant mixture is useful as asolubilizer according to the present invention.

[0020] The solubilizer to be used according to the present invention ispreferably a cryptoanionic surfactant, a non-ionic surfactant, a mixtureof a non-ionic surfactant with an amphoteric surfactant, or a mixture ofa non-ionic surfactant with a cryptoanionic surfactant. A mixture of anon-ionic surfactant with an amphoteric surfactant or a cryptoanionicsurfactant is particularly preferable. The term “cryptoanionicsurfactant” describes anionic surfactants having both anionic andnon-ionic properties, as the anionic character is hidden bycomplexation. The anionic/non-ionic properties are generally influencedby the pH value.

[0021] Preferred solubilizers include surfactants having at least onehydrophobic moiety composed of an alkyl chain or acyl chain having 6 to22 carbon atoms and at least one hydrophilic moiety composed of anoligoethylene oxide chain. Particularly preferred surfactants comprisealkyl ethers or polyglycol ethers from amides derived from carboxylicacids or ether carboxylic acid, ethoxylated glycerides derived fromcarboxylic acids having 6 to 22 carbon atoms and/or alkyl ethercarboxylates derived from alkanols having 6 to 22 carbon atoms.

[0022] As a non-ionic solubilizer, ethoxylated glycerides derived fromcarboxylic acids having 6 to 22 carbon atoms are preferred includingcompounds of the following formula (I):

[0023] wherein each of m, n, and l independently represent a number from0 to 40, the sum of m, n and l being in the range of 1 to 200,preferably 9 to 19; and B1, B2, and B3 independently represent H or anacyl residue having 6 to 22 carbon atoms, with the proviso that at leastone of B1, B2 and B3 is an acyl residue having 6to 22 carbon atoms.

[0024] The ethoxylated glyceride to be used as solubilizer is desirablyused as a mixture of compounds of the above formula (I) comprising

[0025] (i) compounds represented by the above formula (I), wherein eachof B1, B2 and B3 independently represent an acyl group having 6 to 22carbon atoms;

[0026] (ii) compounds represented by the above formula (I), wherein twoof B1, B2 and B3 independently represent an acyl group having 6 to 22carbon atoms, the remainder representing H;

[0027] (iii) compounds represented by the above formula (I), wherein oneof B1, B2 and B3 represents an acyl group having 6 to 22 carbon atoms;the remainder representing H;

[0028] (iv) compounds represented by the following formula (I), whereineach of B1, B2 and B3 represent H;

[0029] the weight ratio of the compounds (i)/(ii)/(iii) being 46 to 90/9to 35/1 to 15.

[0030] These compounds are preferably prepared by a reaction betweentriglyceride and glycerine and ethylene oxide. The preparation of thesecompounds is described in detail in the European Patent EP 0 586 323 B1and in the European Patent Application No. 99 106 233.2.

[0031] The acyl group having 6 to 22 carbon atoms, desirably 12 to 18carbon atoms, is preferably derived from a natural fat or oil or asynthetic glyceride. Preferred fats and oils include vegetable palmkernel oil, sunflower oil, rapeseed oil, castor oil, olive oil, soybeanoil; and animal fat such as tallow, bone oil; fish oil, hardened oilsand semihardened oils thereof; and mixtures thereof. Particularlypreferred are acyl groups derived from coconut oil, palm oil and tallowsuch as beef tallow.

[0032] A particularly preferred ethoxylated glyceride is glycereth-17cocoate, marketed under the trade name Levenol C-201 by Kao S. A. Thisis a mixture of compounds of the above formula (I) wherein the sum of m,n, and 1 is 17 and either one or two groups of B1 and B2 are acyl groupsderived from coconut oil.

[0033] Furthermore, it is preferred to use the ethoxylated glyceride incombination with an amphoteric surfactant such as laurylhydroxysultaine.

[0034] Examples for cryptoanionic surfactants include alkyl ethercarboxylate derived from alkanols having 6 to 22 carbon atoms,preferably those satisfying the following formula (II):

[0035] wherein R is an alkyl residue having 6 to 22 carbon atoms, n hasa value in the range of 5 to 15, more preferably 7 to 10, and M⁺ is anappropriate cation, preferably an alkaline metal cation such as sodiumor potassium.

[0036] Particularly preferred are compounds of the above formula (II)wherein R is an alkyl residue having 8 to 16, more desirably 12 to 14carbon atoms.

[0037] Alkyl ether carboxylates are preferably used as liquidconcentrated aqueous solutions additionally containing non-ionicsurfactants such as ethoxylated products derived from polyhydricalcohols, such as glycerine, that is, compounds of the above formula (I)wherein each of B1, B2 and B3 represent a hydrogen atom, and/orcontaining alcohol ethoxylates, preferably of the formulaR(OCH₂CH₂)_(n)OH, wherein R and n have the same meaning as defined abovefor formula (II). Most preferred are Sodium Laureth-8 Carboxylate(marketed under the trade name {grave over ()}AKYPO SOFT 70 NV by KaoChemicals Europe), a mixture comprising Sodium Laureth-8 Carboxylate andLaureth-7 (marketed under the trade name {grave over ()}AKYPO SOFT 70BVC by Kao Chemicals Europe), and a mixture comprising 30 to 40 wt. %Sodium Laureth-11 Carboxylate, 20 to 30 wt. % Laureth-10 and 5 to 10 wt.% ethoxylated glycerine and carboxymethylated products thereof, thebalance being water and sodium chloride (marketed under the trade nameAKYPO SOFT 100 BVC by Kao Chemicals Europe). The preparation ofcorresponding mixtures is described in EP 0 580 263 B1.

[0038] Furthermore, preferred solubilizers according to the presentinvention include compounds of the following formula (III) (alkyl ethersor polyglycol ethers from amides derived from carboxylic acids or ethercarboxylic acids)

R—O—(CH₂CH₂O)_(m)—CH₂—CO—N(R″)(CH₂CH₂O)_(n)R′

[0039] wherein R is an alkyl group or alkenyl group having 6 to 22,preferably 12 to 18, more preferably 13 to 15 carbon atoms; R′ is ahydrogen atom or an alkyl group or alkenyl group having 6 to 22,preferably 12 to 18, more preferably 13 to 15 carbon atoms; R″ is ahydrogen atom or an alkyl group having 1 to 5 carbon atoms which isoptionally hydroxylated, preferably a hydrogen atom, a methyl group, anethyl group or a hydroxyethyl group; m has a value in the range of 1 to10, preferably 1 to 3, most preferably 2; and n has a value in the rangeof 0 to 10, preferably 0 to 5.

[0040] These compounds are commercially available and are generally soldunder the name Aminol.

[0041] Particularly preferred are compounds of the formula (III) whereinm is 2, n is 1, R represents an alkyl group having 13 to 15 carbonatoms; and both R′ and R″ represent a hydrogen atom.

[0042] Most preferred as compounds of the formula (III) is a compositionmarketed under the name Aminol A15 which is trideceth-2 carboxamide MEA.

[0043] According to the present invention, it is particularly preferredto use the compounds of the formula (III) in combination with theamphoteric or cryptoanionic surfactants such as alkyl ethercarboxylates.

[0044] In the composition of the present invention, the solubilizer isused in a weight ratio of solubilizer to silicone oil in the range offrom 1:1 to 12:1, preferably 2:1 to 8:1. The amount of solubilizer ispreferably 5 to 20 wt. %, more preferably 7 to 15 wt. % with respect tothe total weight of the composition.

[0045] The anionic surfactant as component (c) is not a cryptoanionicsurfactant and is preferably sodium lauryl ether sulfate, preferablyhaving an average degree of ethoxylation of 1 to 3, more preferably 1 to2.5, most preferably 2 to 2.5. The anionic surfactant is desirablycontained in the composition in an amount of 3 to 15 wt. %, preferably 6to 15 wt. %.

[0046] The weight ratio of component (b) to component (c) is within therange of 1:4 to 4:1, preferably 1:2 to 2:1, most preferably in the rangeof 6:7 to 7:6.

[0047] The total amounts of components (b) and (c) is within the rangeof 10 to 25 wt. % with respect to the total weight of the composition,preferably within the range of 12 to 20 wt. %. The total amount of washactive matter, that is, the total amounts of surfactants, contained inthe composition of the present invention is preferably less than 25 wt.%. That is, if the composition contains surfactants other thancomponents (b) and (c), the total amount of these surfactants andcomponents (b) and (c) does desirably not exceed 25 wt. %.

[0048] The compositions of the present invention are opticallytransparent. According to the present invention, the term “opticallytransparent” means that the transmission of the composition in thevisible region is at least 95%. The compositions of the presentinvention have preferably a transmission of more than 97%. Thetransmission is measured according to DIN 53995 using the Dr. LangeLiquid Tester LTM1 (supplied by Dr. Bruno Lange GmbH&Co. KG, Düsseldorf,Deutschland)

[0049] The viscosity of the composition of the present invention ispreferably at least 1500 mPa·s, more preferably 2000-3000 mPa·s. Theviscosity values indicated in the present invention are measured at 20°C. with a Brookfield viscosimeter LVT (supplied by BrookfieldEngineering Laboratories Inc. Stoughton, Mass., USA) in accordance withDIN 1341 (spindle 2 at 30 rpm for viscosities in the range of up to 1000mpa·s; spindle 3 at 12 rpm for viscosities in the range of 1000 to 7000mPa·s; spindle 4 at 12 rpm for viscosities in the range of more than7000 mPa·s).

[0050] The pH value of the composition of the present invention ispreferably within the range of 5 to 8, more preferably 6 to 7.

[0051] Amphoteric surfactant which may be included in the composition ofthe present invention include ampholytes and betaines. Specific examplesare alkyl amine oxides, alkyl betaines, alkyl sulphobetaines(sultaines), alkyl glycinates, alkyl carboxyglycinates, alkylamphoacetates, alkyl amphopropionates, alklyamphoglycinates, alkylamidopropyl betaines, alkyl amidopropyl- and hydroxysultaines.Particularly preferred amphoteric surfactants are alkyl sulphobetaines(sultaines), alklyamphoglycinates and alkyl amphoacetates. Even morepreferred are alkyl hydroxysultaines, in particular laurylhydroxysultaine.

[0052] Amphoteric surfactants are preferably present in a weight ratioof non-ionic or cryptoanionic solubilizer component to amphotericsurfactant in the range of 1:3 to 3:1. The total amount of amphotericsurfactant is preferably between 4 and 8 wt. % with respect to the totalamount of the composition.

[0053] The composition of the present invention may optionally containfatty alcohols having 6 to 22 carbon atoms.

[0054] The compositions of the present applications may also containdeposition polymers. Suitable deposition polymers are any which enhancedeposition of the silicone oil on the intended site, i.e. the hair orthe skin. The deposition polymers disclosed in EP-B-529 883 arepreferably used.

[0055] The composition of the present invention may contain othersurfactants such as cationic surfactants.

[0056] The composition of the present invention preferably also containsa vegetable oil. According to the present invention, the term vegetableoil means a mixture of saturated or unsaturated fatty acids having 6 to22 carbon atoms, triglycerides thereof, esters thereof with alcoholshaving 6 to 22 carbon atoms, and the corresponding fatty alcohols having6 to 22 carbon atoms. The vegetable oil may also be aterpinene-containing oil. Preferred examples of the vegetable oils to beused according to the present invention include evening prime rose oil,sesame oil and preferably jojoba oil, macadamia nut oil, tea tree oil,and avocado oil.

[0057] The vegetable oil is preferably contained in the composition ofthe present invention in a weight ratio of vegetable oil to silicone oilof 1:3 to 3:1, more preferably 1:1. The total amount of silicone oil andvegetable oil is preferably in the range of 2 to 6 wt. % with respect tothe total weight of the composition.

[0058] If vegetable oil is present in the composition of the presentinvention, the hydrophobic silicone oil used is preferably a volatilehydrophobic silicone oil. Volatile hydrophobic silicone oils aresilicone oils which evaporate from the hair surface at atmosphericpressure and room temperature.

[0059] The weight ratio of solubilizer to the total amount of siliconeoil and vegetable oil is preferably in the range of 1:1 to 6:1,preferably 2:1 to 4:1.

[0060] The composition of the present invention may optionally containfurther ingredients such as perfume, preservatives, thickeners, salts,and medically effective substances.

[0061] The preparation of the compositions of the present inventionoften requires a specific preparation method. By simply mixing theingredients in any arbitrary order, the composition of the presentinvention may not always be obtained. This method will now be explainedin more detail.

[0062] The method for preparing the compounds of the present inventioncomprises the steps:

[0063] (a) mixing silicone oil with solubilizer for the silicone oil ina weight ratio of solubilizer to silicone oil in the range of 1:1 to10:1 at a temperature of 20° C. or less; and

[0064] (b) adding anionic surfactant and stirring until an opticallytransparent composition is obtained.

[0065] Step (a) is generally carried out under gentle stirring. Lowstirring energies are not only advantageous in view of energy costs, butparticularly in view of the fact that less air is incorporated into theaqueous solution. Air is generally difficult to remove afterwards fromthe aqueous solution once incorporated and may cause stability problems.

[0066] In the following step (b), the anionic surfactant such as sodiumlauryl ether sulfate is added and the resulting mixture is stirred untilan optically transparent composition is obtained. The anionic surfactantis generally added in diluted form as aqueous solution in aconcentration such that gelation is avoided in step (b). Theconcentration should preferably not exceed 30 wt.-%. Again, it ispreferably only gently stirred in step (b).

[0067] In a further step (c), subsequent to step (b), the viscosity andthe pH of the composition are preferably adjusted to the valuesindicated above. The viscosity of the composition prior to step (c)depends on the components used. If the viscosity is found to beinsufficient, e.g., below 1500 mPa·s, thickeners such as non-ionicsurfactants-type thickeners such as Aminol N, Cocamide DEA and CocamideMEA and derivatives thereof or polymeric thickeners such as PEG-150distearate, PEG-120 methyl glucose dioleate, or PEG-160 sorbitanisostearate may be added. However, the amount of polymeric thickenersshould preferably not exceed an amount of 1 wt.-% with respect to thetotal weight of the composition. Higher amounts of polymeric thickenermay cause an unpleasant sticky feeling on skin during application.

[0068] The pH value may be adjusted to the range of 5 to 8 by adding pHadjusting agents known in the field. Examples for pH adjusting agentsinclude citric acid and NaOH.

[0069] If mixtures of non-ionic surfactants with amphoteric surfactantsor cryptoanionic surfactants are used, the non-ionic surfactants arepreferably added first, the resulting mixtures of silicone and non-ionicare gently stirred, followed by the addition of the amphoteric orcryptoanionic surfactant. Further ingredients such as perfume andpreservations are usually added after step (c).

[0070] The compositions of the present invention show a number ofbeneficial properties in view of their high silicone content, and theymay not only be used as personal care products such as shampoos, hairconditioners, hairdying agents, levelling agents, shower baths, liquidsoaps and other cosmetic rinse-off products, but also in textileapplications (softener) and plastic applications (plastic additives).The compositions are particularly useful as hair gloss shampoos,detangling shampoos, silky hair shampoos, fast drying shampoos, elderlypeople shampoos, colour care shampoos, special care shampoos.

EXAMPLES

[0071] In the Examples, all products used were obtained from KaoChemicals Europe, unless indicated otherwise.

Example 1

[0072] Hair and Scalp Care Shampoo for Elderly People

[0073] Shampoo Recipe Recipe (≈25% Wash Active Matter; ≈29% Total ActiveMatter):

[0074] (1) 25% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0075] (2) 18.5% BETADET S-20 (38% a.m.) (INCI: Lauryl Hydroxysultaine)

[0076] (3) 6% AMINOL N (91% a.m.) (INCI: PEG-4 Rapeseedamide)

[0077] (4) 6% LEVENOL C-201 (100% a.m.) (INCI: Glycereth-17 Cocoate)

[0078] (5) 1.5% Cyclomethicone (IUPAC Decamethylcyclopentasiloxane,saupplied by Dow Corning)

[0079] (6) 1.5% Jojoba oil

[0080] (7) 0.7% RHEODOL TW-IS399C (100% a.m.) (INCI: PEG-160 SorbitanIsostearate) q.s. ad 100%: water, citric acid, perfume, preservative

[0081] Shampoo Preparation:

[0082] (5) and (6) are stirred briefly (≈2 minutes) for intermixing,resulting in a clear liquid

[0083] (4) is added and mixture is stirred briefly (≈3 minutes) forintermixing resulting in a turbid liquid

[0084] (3) is added and stirred briefly (≈4 minutes) resulting in aclear liquid

[0085] (2) is added and stirred briefly (≈3 minutes) resulting in aclear liquid of higher viscosity

[0086] (1) is dissolved in 50% of the water and added together withpreservative to above mixture and stirred for ≈3 minutes resulting in aclear liquid of lower viscosity

[0087] (7) is dissolved in rest of the water at 50° C. & added togetherwith perfume to above mixture and stirred for ≈8 minutes resulting in aclear liquid of suitable viscosity (≈1600 mPas at 20° C.)

[0088] pH-value is adjusted by citric acid (pH: 6-7)

Example 2

[0089] Hair Gloss Shampoo

[0090] Shampoo Recipe Recipe (23% Wash Active Matter; 26% Total ActiveMatter):

[0091] (1) 25% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0092] (2) 18.5% BETADET S 20 (38% a.m.) (INCI: Lauryl Hydroxysultaine)

[0093] (3) 6% LEVENOL C-201 (100% a.m.) (INCI: Glycereth-17 Cocoate)

[0094] (4) 1.5% Phenyl Trimethicone (supplied by Dow Corning)

[0095] (5) 0.5% TETRANYL CO-40 (80% a.m.) (INCI: DioleoylethylHydroxyethylmonium Methosulfate)(

[0096] (6) 3% AMINOL N (91% a.m.) (INCI: PEG-4 Rapeseed amide)

[0097] (7) 0.7% RHEODOL TW-IS399C (100% a.m.) (INCI: PEG-160 SorbitanIsostearate) q.s. ad 100%: water, sodium hydroxide, perfume,preservative

[0098] Shampoo Preparation:

[0099] (5) is dissolved in (4) and stirred briefly (≈3 minutes) forintermixing, resulting in a clear mixture

[0100] (3) is added and stirred for ≈3 minutes, resulting in a clearliquid

[0101] (2) is added and stirred for ≈2 minutes resulting in a moreviscous, turbid liquid

[0102] after addition of (6) and stirring for ≈2 minutes, liquid becomesclear and less viscous again

[0103] (1) is dissolved in 50% of the water and added together withpreservative to above mixture and stirred for ≈3 minutes resulting in aclear liquid of lower viscosity

[0104] (7) is dissolved in rest of the water at 50° C. and addedtogether with the perfume to above mixture and stirred for ≈8 minutesresulting in a clear liquid of suitable viscosity (≈2400 mPas at 20° C.)

[0105] pH-value is adjusted by adding NaOH (50% a.m.)

Example 3

[0106] Hair Gloss Shampoo

[0107] Shampoo Recipe (≈19% Wash Active Matter; ≈22% Total ActiveMatter)

[0108] (1) 25% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0109] (2) 5% AKYPO SOFT 70 BVC (70% a.m.) (INCI: Sodium Laureth-8Carboxylate (and) Laureth-7)

[0110] (3) 5% AKYPO SOFT 100 BVC (70% a.m.) (INCI: Sodium Laureth-11Carboxylate (and) Laureth-10)

[0111] (4) 1% jojoba oil

[0112] (5) 1% Cyclomethicone ((IUPAC: Decamethylcyclopentasiloxane;supplied by Dow Corning)

[0113] (6) 5% AMINOL N (91% a.m.) (INCI: PEG-4 Rapeseedamide)

[0114] (7) 1% PEG-150 Distearate

[0115] (8) 3% sodium chloride

[0116] q.s. at 100% : water, perfume, preservative , citric acid

[0117] Shampoo Preparation:

[0118] (4) and (5) are stirred briefly (≈5 minutes) for intermixing

[0119] (2) and (3) are added and stirred until a homogeneous mixture isobtained (≈10 min)

[0120] (7) and water are heated to 50° C. until (7) dissolved (≈20 min),followed by addition of (1) and stirring for ≈5 minutes,

[0121] followed by addition of (6) (≈20 minutes stirring) and

[0122] addition of preservative and perfume at a temperature below 30°C.

[0123] this mixtures (containing the components (7), (1) and (6) isadded to the mixture containing the components (2) to (5) obtained aboveand stirring is continued until a homogeneous mixture is obtained (≈20min)

[0124] the pH-value is adjusted by adding citric acid (pH: 6-7) andviscosity (≈3000 mPas at 20° C.) is adjusted by addition of (8)

Example 4

[0125] Fast Drying Hair Shampoo

[0126] Shampoo Recipe (≈24% Wash Active Matter; ≈27% Total ActiveMatter):

[0127] (1) 12.5% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0128] (2) 20% AKYPO SOFT 100 BVC (70% a.m.) (INCI: Sodium Laureth-11Carboxylate (and) Laureth-10)

[0129] (3) 1% AKYPO QUAT 132 (70% a.m.) (INCI: Lauroyl PG-TrimoniumChloride)

[0130] (4) 6% AMINOL A 15 (97% a.m.) (INCI: Trideceth-2 Carboxamide MEA)

[0131] (5) 2% Cyclomethicone (IUPAC: Decamethylcyclopentasiloxane;supplied by Dow Corning)

[0132] (6) 1% RHEODOL TW-IS399C liquid (61.5% a.m.) ( PEG-160 SorbitanIsostearate

[0133] (7) 3.5% sodium chloride q.s. at 100%: water, perfume,preservative

[0134] Shampoo Preparation:

[0135] (4) and (5) are stirred briefly (2 minutes) for intermixing

[0136] (2) is added while stirring and stirring is continued for 2minutes

[0137] (1) is dissolved in the water (to avoid gelation) and added tothe above mixture while stirring (≈20 minutes), followed by addition of(3) and further stirring for ≈10 minutes.

[0138] (6) is added, followed by adding perfume and preservative and

[0139] viscosity adjustment by (7) (2000-3000 mPas at 20° C.).

Example 5

[0140] Foaminess

[0141] For demonstrating the low foaminess reducing effect ofsolubilized Cyclomethicone compared to emulsified one, a number offormulations were prepared as described above for Example 4:

[0142] Composition (2a):

[0143] (1) 16% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0144] (2) 6% AKYPO SOFT 100 BVC (70% a.m.) (INCI: Sodium Laureth-11Carboxylate (and) Laureth-10)

[0145] (3) 6% AKYPO SOFT 70 BVC (70% a.m.)

[0146] (4) 3% AMINOL A 15 (97% a.m.) (INCI: Trideceth-2 Carboxamide MEA)

[0147] (5) ad 100%: water, perfume, preservative

[0148] Composition (2b):

[0149] same basic composition as composition (2a), but additionallycontaining 2.5% of cyclomethicone

[0150] Composition (2c):

[0151] (1) 13% EMAL 228D (28% a.m.) (INCI: Sodium Laureth Sulfate)

[0152] (2) 5% AKYPO SOFT 100 BVC (70% a.m.) (INCI: Sodium Laureth-11Carboxylate (and) Laureth-10)

[0153] (3) 5% AKYPO SOFT 70 BVC (70% a.m.)

[0154] (4) 5% AMINOL A 15 (97% a.m.) (INCI: Trideceth-2 Carboxamide MEA)

[0155] (5) ad 100%: water, perfume, preservative

[0156] Composition (2d):

[0157] same basic composition as composition (2c), but additionallycontaining 2.5% of cyclomethicone

[0158] The foaminess of the compositions (2a) to (2d) was determined bythe Ross Miles Test (DIN 53902; 0.1% a.m.; 25° C.; 15° gh)). Thedifferences in foaminess due to the presence of the silicone oil werefound to be negligible (composition (2a): 197 mm; composition (2b): 187mm; composition (2c): 186 mm; composition (2d): 177 mm) and comparableto a Sodium Laureth Sulfate/Cocamidopropyl Betaine based shampoo withoutsilicone oil.

1. An optically transparent aqueous composition comprising (a) ahydrophobic silicone oil in an amount of 1-3 wt.-% with respect to thetotal weight of the composition; (b) a solubilizer for the silicone oil;and (c) an anionic surfactant; wherein the weight ratio of component (b)to component (a) is in the range of 1:1 to 12:1; and wherein the totalamount of the components (b) and (c) is in the range of 10-25 wt.-% withrespect to the total weight of the composition.
 2. The aqueouscomposition according to claim 1, wherein the solubilizer is acryptoanionic surfactant, a non-ionic surfactant, a mixture of anon-ionic surfactant with an amphoteric surfactant, or a mixture of anon-ionic surfactant with a cryptoanionic surfactant.
 3. The aqueouscomposition according to claim 2, wherein the solubilizer comprises analkyl ether carboxylate derived from alkanols having 6 to 22 carbonatoms.
 4. The aqueous composition according to claim 2 and 3, whereinthe solubilizer is a mixture of alkyl ether carboxylate derived fromalkanols having 6 to 22 carbon atoms with ethoxylated products derivedfrom polyhydric alcohols.
 5. The aqueous composition according to claim2, wherein the solubilizer comprises an ethoxylated glyceride derivedfrom carboxylic acids having 6 to 22 carbon atoms.
 6. The aqueouscomposition according to claim 5, wherein the solubilizer comprisesglycereth-17 cocoate.
 7. The aqueous composition according to claim 2,wherein the solubilizer comprises a compound of the following formula(III): R—O—(CH₂CH₂O)_(m)—CH₂—CO—N(R″)(CH₂CH₂O)_(n)R′ wherein R is analkyl group or alkenyl group having 6 to 22, preferably 12 to 18, morepreferably 13 to 15 carbon atoms; R′ is a hydrogen atom or an alkylgroup or alkenyl group having 6 to 22, preferably 12 to 18, morepreferably 13 to 15 carbon atoms; R″ is a hydrogen atom or an alkylgroup having 1 to 5 carbon atoms which is optionally hydroxylated,preferably a hydrogen atom, a methyl group, an ethyl group or ahydroxyethyl group; m has a value in the range of 1 to 10, preferably 1to 3, most preferably 2; and n has a value in the range of 0 to 10,preferably 0 to
 5. 8. The aqueous composition according to claim 7,wherein the solubilizer comprises a compound of the formula (III)wherein m is 2, n is 1, R represents an alkyl group having 13 to 15carbon atoms; and both R′ and R″ represent a hydrogen atom.
 9. Theaqueous composition according to any of the preceding claims, whereinthe hydrophobic silicone oil is a non-volatile silicone oil.
 10. Theaqueous composition according to any of the preceding claims,additionally containing a vegetable oil.
 11. The aqueous compositionaccording to claim 10, wherein the hydrophobic silicone oil is avolatile silicone oil.
 12. The aqueous composition according to claim 2,wherein the amphoteric surfactant is lauryl hydroxysultaine.
 13. Theaqueous composition according to claim 2 or 12, wherein the amphotericsurfactant is present in an amount of 4 to 8 wt.-% with respect to thetotal weight of the composition.
 14. The aqueous composition accordingto any of the preceding claims, wherein the anionic surfactant is sodiumlauryl ether sulfate having an average degree of ethoxylation in therange of 1 to
 3. 15. The aqueous composition according to any of thepreceding claims, wherein the composition has a viscosity of at least1500 mPa s.
 16. The aqueous composition according to any of thepreceding claims, wherein the composition has a a pH value in the rangeof 5 to
 8. 17. Method for preparing a composition according to claim 1,comprising the steps of: (a) mixing silicone oil with a solubilizer forthe silicone oil in a weight ratio of solubilizer to silicone oil in therange of 1:1 to 12:1 at a temperature of 20° C. or less; and (b) addinganionic surfactant and stirring until an optically transparentcomposition is obtained.
 18. Hair shampoo comprising the composition ofany of claims 1 to 16.